The invention concerns a piezoresistive measuring cell having a measuring membrane or diaphragm provided with resistance elements and with conductors extending from contact points on the resistance element to the measuring membrane.
A pressure measuring element with a pressure measuring cell of this type has already been disclosed in German Pat. specification No. 26 30 640. This previously known pressure measuring element is disposed in a transmitting membrane or diaphragm housing in either cylindrical or essentially cylinder-like form, and with the housing being closed off at its top face side by a transmitting diaphragm. Installed below the transmitting diaphragm with resistances provided on its top side is the reference pressure measuring cell. The referenced cell is attached to a discoid glass feedthrough base through which run some base pins with the base pins extending in the axial direction next to the pressure measuring cell.
On their side facing toward the diaphragm, the base or socket pins are coupled to the resistance on the pressure measuring cell by means of connecting wires. In order to apply these features or principles for pressure measuring cells suited for absolute as well as for differential pressure measurements for a wide variety of ranges, it is, however, necessary to completely manufacture the pressure measuring element, including the base with the glass feedthroughs for the base pins and the connecting wires (which generally consist of gold). This arrangement is then delivered to original equipment manufactures who then may build this pressure measuring element into a membrane or diaphragm housing, in accordance with the specific objectives of the device. Soldering of the bonding wires requires cost-intensive, precision machines whose procurement price can cost many thousands of dollars.